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Discovering the causes of cancer and the means of prevention

Current Fellows in the Radiation Epidemiology Branch

Meet the current fellows in the Radiation Epidemiology Branch and learn about research training opportunities.

Elizabeth (Lisa) Khaykin Cahoon, Ph.D., S.M., M.H.S. - Research Fellow

portrait of Elizabeth Cahoon

Elizabeth Khaykin Cahoon, Ph.D., S.M., M.H.S., joined the Radiation Epidemiology Branch (REB) as a postdoctoral fellow in July 2010. Dr. Cahoon received her master’s in biostatistics in 2005 and her Ph.D. in epidemiology in 2008, both from the Johns Hopkins Bloomberg School of Public Health. Her doctoral research involved examining patient safety in persons with serious mental illness. While at Johns Hopkins, Dr. Cahoon also conducted a meta-analysis on secondhand smoking and cancer for the U.S. Surgeon General’s report on The Health Consequences of Involuntary Exposure to Tobacco Smoke, contributed to writing of The International Agency for Research on Cancer, World Health Organization monograph on secondhand smoking and cancer, and researched the history of radon and cancer. Dr. Cahoon worked under the mentorship of Jonathan Samet, M.D., M.S., Department of Epidemiology Professor and Chair, Gail Daumit, M.D., M.H.S., Associate Professor of Medicine, and William Eaton, Ph.D., Department of Mental Health Professor and Chair during her time at Hopkins. In REB, Dr. Cahoon works with her primary mentor D. Michal Freedman, J.D., M.P.H., Ph.D., epidemiologist, evaluating cancer risks associated with medication use, ultraviolet radiation, and vitamin D in the United States Radiologic Technologists cohort. Dr. Cahoon also works with Kiyohiko Mabuchi, M.D., Dr.P.H., Deputy Chief of REB, head of the Chernobyl Research Unit, and senior scientist, and Alina V. Brenner, M.D., Ph.D., M.P.H., staff scientist on assessment of risks of thyroid cancer and related diseases in cohorts of persons exposed to radiation as a result of the Chernobyl accident.

DCEG Publications (text and abstracts from our publications database)

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Lienard Chang, M.S. – Postbaccalaureate Fellow

portrait of Lienard Chang

Lienard Chang joined the Radiation Epidemiology Branch (REB) as a postbaccalaureate fellow in December 2013. Mr. Chang obtained his B.S. in nuclear engineering from Pennsylvania State University in May 2013 and M.S.  in health physics from Georgetown University in March 2015. His master’s thesis focused on calculating organ dose conversion coefficients for reference pediatric phantoms in external photon radiation fields. Throughout his education and work experience, Mr. Chang has worked on projects involving: power plant design recommendations in response to the Fukushima Daiichi accident; boron and xenon concentrations as functions of nuclear power cycle burn-up; liquid scintillation counting in research of nicotine receptors; and MARSSIM-based decommissioning. In REB, he is working primarily with Choonsik Lee, Ph.D., investigator, and Steve Simon, Ph.D., staff scientist, and is focusing on projects regarding external and medical dosimetry. One major project involves estimating organ doses for pediatric computational phantoms exposed to external photon radiation fields in the event of radiological accidents or attacks.

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Neige Journy, Ph.D., M.P.H., Postdoctoral Fellow

portrait of Neige Journey

Neige Journy, Ph.D., M.P.H, joined the Radiation Epidemiology Branch (REB) as a postdoctoral fellow in March 2015. She received a master’s degree in public health from the Bordeaux School of Public Health, France, prior to completing an M.P.H in biostatistics and Ph.D. in epidemiology from the Paris-Sud University in France. Her doctoral research focused on childhood cancer risks following CT scan exposures. This work was conducted at the French Institute for Nuclear Safety and Radiation Protection under the mentorship of Dr. Marie-Odile Bernier, M.D, M.P.H, and Dr. Dominique Laurier, Ph.D., both of the Laboratory of Epidemiology. In REB, she is involved in studies on cancer risk assessment after diagnostic and therapeutic medical exposures under the mentorship of Dr. Amy Berrington de González, D. Phil., REB Branch Chief.

Scientific Publication

Clara Kim Lam, M.P.H. - Predoctoral Fellow

Clara Kim

Clara Kim, M.P.H., is a predoctoral fellow in the Radiation Epidemiology Branch (REB) and is enrolled in the Ph.D. program in cancer epidemiology at the George Washington University School of Public Health and Health Services. Ms. Kim received a B.S. in biology and psychology from Brandeis University in 2005 and an M.P.H. in epidemiology from the George Washington University in 2009. For her M.P.H. final thesis she examined the significance of microRNA in the insulin pathway and the association with diabetes. Ms. Kim is working under the mentorship of Lindsay Morton, Ph.D., investigator, REB, to identify patterns of and risk factors for multiple primary cancers among patients with at least one hematologic malignancy.


Publications in PubMed

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Terrence Lee, Ph.D. - Postdoctoral Fellow

Terrence Lee

Terrence Lee, is a postdoctoral fellow in the Radiation Epidemiology Branch (REB). Dr. Lee successfully completed a Ph.D. program in occupational and environmental epidemiology at the Johns Hopkins Bloomberg School of Public Health in 2014. Mr. Lee received a B.S. in food biochemistry from the University of California at Davis in 1988 and an M.P.H. in epidemiology from the University of California at Los Angeles in 1990. He was also a postgraduate environmental health and industrial hygiene fellow at the Uniformed Service University for the Health Sciences in 1997. Mr. Lee served as a civilian epidemiologist with the U.S. Army for over 10 years; he also worked as a medical surveillance coordinator at the U.S. CDC in Beijing, China. Mr. Lee works with Mark Little, D.Phil., senior investigator, REB, and Alice Sigurdson, Ph.D., staff scientist, REB, on his doctoral dissertation which will use the U.S. Radiologic Technologist cohort to examine the risk factors for basal cell carcinoma and risk of subsequent cancer for those with basal cell carcinoma.

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Hyeyeun Lim, Ph.D., M.P.H., - Postdoctoral Fellow

Hyeyeun Lim, Ph.D., M.P.H., joined the Radiation Epidemiology Branch (REB) as a postdoctoral fellow in December 2014.   Dr. Lim received a B.A. in Health Science from Dongduk Women’s University, South Korea, an M.P.H. in environmental and occupational health science from Emory University (2010), and a Ph.D. in Environmental and Occupational Health from the University of Texas, Houston (2014).  For her doctoral work, Dr. Lim evaluated the association between maternal exposure to ionizing radiation during the periconceptional period and selected birth defects in offspring using data from National Birth Defects Prevention Study.  In REB, she is working under the mentorship of Martha Linet, M.D., M.P.H., senior investigator, REB, and Cari Kitahara, Ph.D., research fellow, REB, on evaluating cancer risks associated with diagnostic procedures in the United States Radiologic Technologists Cohort.

Publications in PubMed

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Jason Liu, Sc.D., M.S., - Postdoctoral Fellow

portrait of Jason Liu

Jason Liu, Sc.D., M.S., joined the Radiation Epidemiology Branch (REB) as a postdoctoral fellow in the summer of 2012. Dr. Liu received a B.S. in cellular and molecular biology from the University of Michigan – Ann Arbor, an M.P.H. in epidemiology from Columbia University, and an M.S. in biostatistics and Sc.D. in epidemiology from Harvard University. For his doctoral thesis, he examined the influence of vitamin D and one-carbon metabolism factors on telomere length and endometrial cancer. In DCEG, he is working under the mentorship of Martha Linet, M.D., M.P.H., Chief of REB, and senior investigator, on the U.S. Radiologic Technologists Study to determine the role of occupational radiation exposure on cancer incidence and mortality.


Publications in PubMed

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Wayne Liu, B.S. Postbaccalaureate Fellow

Wayne Liu joined the Radiation Epidemiology Branch (REB) as a postbaccalaureate fellow in September of 2014. He received his B.A. in Public Health Studies at Johns Hopkins University in 2014. Mr. Lui was a DCEG summer fellow in 2012, working with , staff scientist, REB, to examine thyroid conditions and thyroid cancer risk from U.S. atomic bomb testing. Currently, Mr. Liu is working with Elizabeth Cahoon, Ph.D., research fellow, REB, examining the role of ionizing radiation and risk of skin cancers in the U.S. Radiologic Technologists cohort. He will also study the effect of ultraviolet radiation and the risk of digestive cancers in U.S. veterans.

 


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Emily McDonald Bowen, M.P.H. – Postbaccalaureate Fellow

portrait of Emily McDonald Bowen

Emily McDonald Bowen, M.P.H., joined the Radiation Epidemiology Branch (REB) in August 2014 as a postbaccalaureate fellow. She received a B.A. in geology from Middlebury College in 2012 and an M.P.H. in epidemiology from Indiana University in 2014. She worked as a DCEG Summer Fellow in REB in 2013 under the mentorship of Elizabeth Khaykin Cahoon, Ph.D., S.M., M.H.S., research fellow, and Michal Freedman, J.D., Ph.D., M.P.H., epidemiologist. In that role, Ms. Bowen completed a study investigating the relationship between prescription diuretic use, a photosensitizing medication, ultraviolet radiation exposure and basal cell carcinoma in the U.S. Radiologic Technologists Study. She has a strong interest in environmental sources of radiation and its effect on health. During her fellowship, Ms. Bowen will continue to work primarily with Drs. Cahoon and Freedman to investigate the relationship between ultraviolet radiation exposure and cancer risk.

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Dayton McMillan, M.S. - Postbaccalaureate Fellow

portrait of Dayton McMillan

Dayton McMillan, M.S., joined the Radiation Epidemiology Branch (REB) as a postbaccalaureate fellow in June 2014. Mr. McMillan received a B.S. in environmental health and an M.S. in radiological health sciences from Colorado State University in May 2014. His M.S. thesis focused on evaluating the Cu-ATSM imaging agent for radiotherapy purposes. Mr. McMillan has also conducted additional research in areas of health and medical physics. Currently he works with Choonsik Lee, Ph.D., investigator, REB, on dose reconstruction research associated with medical imaging and radiotherapy applications. His current project entails comparison of simulated patient organ doses from modulated versus conventional computed tomography scans.


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Estelle Ntowe, M.H.S. – Postbaccalaureate Fellow

portrait of Estelle Ntowe

Estelle Ntowe, M.H.S.,joined the Radiation Epidemiology Branch (REB) in October 2013 as a postbaccalaureate fellow. Ms. Ntowe earned her M.H.S in Environmental Health Sciences from the Johns Hopkins Bloomberg School of Public Health in 2013. She graduated from Penn State University with a bachelor’s degree in life sciences in 2009. Ms. Ntowe is working with Amy Berrington de González, D.Phil., Chief of REB, on radiation-induced cancers in an epidemiological cohort of radiologists and physicians performing fluoroscopically guided procedures. Ms. Ntowe also is conducting an analysis of radiotherapy modalities and second cancer risks in the Surveillance, Epidemiology, and End Results (SEER) Medicare database. In addition, she assists in projects assessing second cancer risk in the Kaiser Breast Cancer Survivors cohort.

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Kamau O. Peters, Ph.D., M.P.H. – Postdoctoral Fellow

portrait of Kamau Peters

Kamau O. Peters, Ph.D., M.P.H., joined the Radiation Epidemiology Branch (REB) as a postdoctoral fellow in April 2015.He earned his Ph.D. in environmental health sciences from the Johns Hopkins Bloomberg School of Public Health. Working with Paul T. Strickland, Ph.D., his doctoral research focused on polycyclic aromatic hydrocarbon exposures, inflammation, and asthma exacerbation in children and adults with asthma from Baltimore, MD. Dr. Peters earned an M.P.H. in toxicology from the University of Michigan School of Public Health in 2003. He is currently working with Maureen Hatch, Ph.D., staff scientist, REB, and the Chernobyl Research Unit (CRU) of REB to investigate thyroid disease following exposures to fallout from the Chernobyl nuclear power plant accident.


Publications in PubMed

Anil Prasad Pyakuryal, Ph.D., M.S. - Postdoctoral Fellow

portrait of Anil Pyakuryal

Anil Prasad Pyakuryal, Ph.D., M.S., joined the Radiation Epidemiology Branch (REB) as a visiting fellow in April 2014. Dr. Pyakuryal earned an M.S. in electrical engineering from Southern Illinois University at Carbondale in 2002. He received his Ph.D. in physics with a research concentration in radiation oncology physics from the Northwestern Memorial Hospital/University of Illinois at Chicago in 2011. His post-doctoral training focused on applying computational phantoms to understand radiation toxicity and secondary cancer after conventional and advanced radiation therapy. Dr. Pyakuryal works under the mentorship of Choonsik Lee, Ph.D., investigator, REB, on projects related to organ dose reconstruction for radiotherapy patients. Their work includes a collaboration with the NIH Clinical Center.

Publications in PubMed

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Rachel Zamoiski, Ph.D. - Postdoctoral Fellow

Rachel Zamoiski, Ph.D., joined the Radiation Epidemiology Branch (REB) as a postdoctoral fellow in November 2014. Dr. Zamoiski received her Ph.D. in environmental health sciences from the Johns Hopkins Bloomberg School of Public Health (JHSPH) in 2014. Her doctoral dissertation work was focused on studying exposures to heavy metals, vitamin D levels, and inflammation. Dr. Zamoiski also has an M.P.H. from the JHSPH (2007) and a B.A. in Psychology from the University of Pennsylvania (2004). In REB, Dr. Zamoiski is working with Martha Linet, M.D., M.P.H., senior investigator, REB and D. Michal Freedman, J.D., M.P.H., Ph.D., epidemiologist, REB, on cancer risks associated with ultraviolet radiation in the United States Radiologic Technologists Cohort.


Publications in PubMed

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